JPS62122691A - Automatic sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic sewing machine that forms a predetermined number of stitches and then stops while moving a holder holding a workpiece in a horizontal direction with respect to a needle drop position.

Conventionally, the above-mentioned automatic sewing machines include bar tacking machines,
There are buttonhole sewing machines, button sewing machines, embroidery sewing machines, and other zaik/l/stitch sewing machines.In recent years, a pair of pulse motors that drive in each of the x and y directions are connected to a holder that holds the sewing material. Electrically controlled sewing machines are known in which a holding body is moved in the XY direction under the control of a pulse motor to form stitches of a predetermined shape. However, in this conventional electrically controlled sewing machine, a connecting member such as a timing belt or chain is required between both pulse motors and the holder, making the structure complicated and difficult to assemble. As the number of connecting members increases, errors tend to occur between the step position of the motor and the moving position of the holder, making the needle drop position inaccurate and bar tacking.

In embroidery sewing machines, the warp shape may be distorted, and in buttonhole sewing machines, the needle may drop into the area where the incision is to be made and the sewing thread may be later cut by a knife, resulting in a significant deterioration in the quality of the sewn product.

This invention aims to eliminate the drawbacks of the above-mentioned conventional ones.

An embodiment of the present invention will be described with reference to the drawings. 1 is the main body of the bar tack sewing machine, 2 is the bed of the sewing machine 1, 3 is an arm facing parallel to the top of the bed 2, and 4 is a sewing machine main shaft (not shown) at the tip of the arm 3. The needle bar moves up and down in conjunction with the
5 is a needle that is fixed to the lower end of the needle bar 4 and cooperates with a shuttle mechanism (not shown) below the bed 2; 6 is a needle that is fixed to the lower end of the needle bar 4 and works with the hook mechanism (not shown) below the bed 2; This is a presser foot that is movably supported and constantly receives downward elastic force.

Inside the bed 2, reference numeral 7 denotes a support shaft having a horizontal axis extending in a direction crossing the longitudinal direction of the bed 2 and fixed to the machine frame, and 8 a support plate rotatably supported at one end edge around the support shaft 7. , 9 is a support stand which is fixed on the holding plate 8 and has a substantially U-shaped cross section and has a pair of legs 9α and 9A that are opposed to each other in the longitudinal direction of the bed 2 and protrude upward; 10 is a support stand inside the support stand 9; 9
11 is a drive shaft of the stepping motor 10, 12 is a main gear fixed to the drive shaft 11, and 13 is a stepping motor that is fixed vertically and protrudes from the upper end of one leg 96 of the support base 9. A support shaft 14 having an axis is rotatably supported on the support shaft 13, and has a first tooth portion 14α having a larger diameter than the main gear 12 and is screwed onto the main gear 12, and a first tooth portion 14a located at the upper end. This is a follower gear in which a second tooth portion 14h is formed with a diameter smaller than that of the portion 14α. 15 is the other leg 9h of the support stand 9
A support shaft protruding from the upper end and fixed and having a vertical axis; 16, an action plate supported opposite to a hole 2α formed in the upper surface of the bed 2, so as to be rotatable on the base end side about the support shaft 15; 17, a support shaft; axis 1
A protruding portion 18 and 19 is a protruding portion that protrudes downward from the action plate 16 along an arc centered at 5 and has a tooth portion 17α that is threadedly engaged with the second tooth portion 14bK of the follower gear 14 on the inner end surface. Each pair of pillars stands upwards.

20 is a linear pulse motor consisting of a fixed body 21 fixed to the upper end 1c of the column 18.19, and a movable body 22 supported so as to be movable in a straight line along the longitudinal direction of the bed 2 relative to the fixed body 21. Its basic structure is as follows. As shown in the figure 1 moving body 2
The movable element 50 provided on the fixed body 21 is made of a soft magnetic material, and its upper and lower surfaces are shaped like comb teeth with an equal pitch. is shown only on the top side) Symmetrical three-cylinder yokes 51α, 51
b, forming 51C, and its six pairs of yokes 51α.

The tip surfaces of 5iA and 51c are formed with comb teeth, and the comb teeth are arranged so that each comb tooth of one of the yokes faces the comb teeth of the movable element 50. 51
α, 51A, 51c have coils 52α, 52b, 52c
Wrap it around. The linear pulse motor 20 and the pulse motors 10 and K are each provided with detection means (not shown) for detecting the operating position.

A frame-shaped cloth presser (holding body) 23 is formed at the tip of the movable body 22 facing the needle drop point, and the cloth is held between it and the upper surface of the bed 2 so that the cloth can be moved horizontally.

Reference numeral 24 denotes an electromagnet fixed to the machine frame opposite to the upper surface of the tip side of the retaining plate 8, and the retaining plate 8 always has an elastic force that moves the presser foot 23 away from the upper surface of the bed 2 in the clockwise direction in FIG. A force is applied, and when the electromagnet 24 is energized, the holding plate 8 is rotated counterclockwise (FIG. 2) against this elastic force to press the presser foot 23 against the upper surface of the bed 2. Reference numeral 25 denotes a large number of manual switches 26 for setting the sewing shape, number of stitches, sewing pitch, etc., and display means for displaying the settings of the manual switches 25, etc.

Although not shown, the main shaft of the sewing machine includes a needle position detection means that generates a signal at a predetermined rotation angle during rotation of the main shaft;
A rotational position detection means for detecting the step position of the stepping motor 10, and a movement position detection means for detecting the step position of the linear motor 20 are arranged.

Next, the circuit shown in FIG. 5 will be explained.

CD is an operation setting circuit having an input section for inputting setting data related to the operation of the manual switch 25 and a display section for displaying the input contents on the display means 26, SC is a detection circuit including each of the above-mentioned detection means, and DS is a stepping circuit. The drive circuit DR generates step pulses for driving the motor 10 in the coils of each phase, and the DR generates step pulses for driving the linear pulse smoke 20 in the coils 52 . ~52. ．． A drive circuit generated at - and DM is an operating circuit that de-energizes the electromagnet 24.

MC is a microcomputer (microcomputer and slot) connected to each circuit via an input/output circuit 0, and in order to form a seam line of a predetermined shape based on the settings from the operation setting circuit SC, as shown in FIG. The sewing machine is driven by the main 70-.

That is, when a start signal related to the operation of a pedal or the like is generated, the actuating circuit DM acts to energize the electromagnet 24, and then after forming a stitch of a predetermined shape according to the "sewing routine", the electromagnet 24 is activated. The actuating circuit DM acts to deenergize. The "sewing routine" sets data such as the number of stitches, sewing pitch, and feed direction so that a predetermined stitch line is obtained based on the settings from the operation setting circuit SC.Based on the data, the sewing machine is stopped and the needle position is set. The surface drive circuits DR and DS are controlled to set the number of step pulses to the stepping motor 10 and the linear pulse motor 20 so as to move the presser foot 23 to each needle drop position in relation to the signal generation from the detection means. .

The present invention has the above-described structure, and the holding plate 8 normally rotates clockwise in FIG. In connection with this, the shape, number of stitches, sewing pitch, etc. are set.

When a starting signal is generated by operating a pedal or the like, the electromagnet 24 is energized by the signal from the operating circuit DM, and the holding plate 8
is rotated counterclockwise (Fig. 2) against the elastic force, and the presser foot 23 clamps the material to be sewn (cloth) and is pressed against the upper surface of the bed 2, and then the "sewing routine" is processed. Ru.

The sewing machine 1 is driven, the main shaft of the sewing machine rotates, the needle bar 4 moves up and down, and a stitch is formed by the cooperation of the needle 5 and the shuttle mechanism. Data is sequentially read from the microcomputer MC in relation to the needle position signal, and based on the data, the surface drive circuits DS and DR perform a predetermined number of steps to move the presser foot 23 to the next needle drop position. A pulse is generated. When the stepping motor 10 performs step driving, the rotation of the main gear 120 causes the first tooth portion 14 to be threadedly engaged with the main gear 120. through the follower gear 14
The rotation of the driven gear 14 is further transmitted to the second gear 14A.
The information is transmitted to the action plate 16 through the toothed portion 17α on the circular arc that is screwed into the action plate 16, and the action plate 16 rotates through a predetermined rotation angle corresponding to the step angle around the support shaft 15, thereby moving the cloth presser portion 23 to the second position. Move in the Y direction in Figure 1.

Further, by step driving of the linear pulse motor 20, the movable body 22 moves in the left-right direction in FIG. 2, and the cloth presser foot 23 at the tip of the movable body 22 moves in the Y direction in FIG. 1. A predetermined number of stitches are sequentially formed with the movement point resulting from the combination of movements in both the X and Y directions as the next needle drop position, and when the predetermined number of stitches have been formed, the [sewing routine] ends, and the operation circuit DM
The electromagnet 24 is deenergized by a signal from the sewing machine, and the holding plate 8 returns clockwise due to its elastic force, and the presser foot 23 is separated upward from the upper surface of the bed 2 to release the material to be sewn.

In this embodiment, the cloth presser 23 is integrally formed at the tip of the moving body 22 of the linear pulse motor 20, but a separate cloth presser may be fixed to the tip of the moving body 22.

Also, the main gear 1 on the drive shaft 11 of the stepping motor 10
2 is screwed onto the teeth 17a of the action plate 16 via the slave gear 14, but the main gear 12 may be screwed directly onto the teeth 17a.

Further, instead of the present embodiment, the presser foot may be moved by two linear pulse motors as shown in the seventh factor. That is, the support stand 2 on the holding plate B of this embodiment for one linear pulse motor 27 is located below the sewing machine bed.
A fixed body 29 having the same configuration as the moving body 22 of this embodiment is fixed to 8, and a moving body 30 having the same configuration as the fixed body 21 of this embodiment in the longitudinal direction (sewing machine A linear pulse motor 31 (defining body 62, movable body 63) having the same configuration as the linear pulse smoke 20 of this embodiment is supported so as to be movable in the
(combination with) is fixed.

Step pulses are supplied to both linear motors 27 and 31 to move the cloth presser body 64 at the tip of the movable body 66 to a combined movement position in both directions of X7.

Further, in this embodiment, a bar tack sewing machine has been described, but the present invention may be applied to other sewing machines such as an embroidery line sewing machine, a buttonhole sewing machine, and a button sewing machine.

As described above, according to the present invention, there is provided a pulse motor (10) which is arranged below the sewing machine bed and has a slider that rotates around a vertical axis, and a pulse motor (10) that is connected to the slider of the pulse motor and is rotatable around the vertical axis. A working body (16) is supported on the machine frame, and a linear pulse is arranged above the sewing machine bed, and a stator is fixed to the working body, and the mover can be moved linearly along the main axis of the sewing machine and parallel to the upper surface of the sewing machine bed. A motor (20), a cloth holder that holds the material to be sewn and is connected to the mover of the linear balsmower so that it can be moved along the top surface of the sewing machine bed to the needle drop position, and a cloth holder that holds the material to be sewn every rotation of the main shaft of the sewing machine. By providing a control circuit that separately generates a predetermined number of step pulses for both motors to move the body to a predetermined position relative to the needle drop position, a timing belt or chain is no longer required, simplifying the structure. This has the effect of making assembly easier, and since there are fewer connecting members between the holder and both motors, the motor can be moved without making any errors between the step positions and the sewing shape is beautiful. Also, since the seam threads are not damaged, the quality of the product can be significantly improved.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the bar tack sewing machine of this embodiment, Fig. 2 is a partial end view, Fig. 6 is an end view taken along the line Z-Z in Fig. 2, and Fig. 4 is an explanation showing the basic structure of the linear pulse motor. 5 is a circuit diagram of this embodiment, FIG. 6 is a main flowchart included in the microcomputer MC, and FIG. 7 is a perspective view of another embodiment.

Claims (1)

[Scope of Claims] A pulse motor (10) that is disposed below the sewing machine bed and has a slider that rotates around a vertical axis, and is connected to the slider of the pulse motor and supported on the machine frame so as to be rotatable around the vertical axis. a linear pulse motor (20) which is arranged above the sewing machine bed and has a stator fixed to the working body and whose movable element can be moved linearly along the sewing machine main axis and parallel to the upper surface of the sewing machine bed; A fabric holder that holds the sewing material and is connected to a slider of a linear pulse motor so that it can be moved along the top surface of the sewing machine bed relative to the needle drop position, and the holder is moved to a predetermined position relative to the needle drop position each time the main shaft of the sewing machine rotates. An automatic sewing machine equipped with a control circuit that separately generates a predetermined number of step pulses to both motors so that the motors move.